Phase behaviour and structure of a non-ionic discoidal amphiphile in water

Boden, N.; Bushby, Richard J.; Hardy, Cordell M.; Sixl, F.

doi:10.1016/0009-2614(86)80021-5

Cited by 55 publications

(40 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…12,16 Several attempts have been made to study TP6EO2M molecules theoretically 18,19 and by computer simulations. 20, 21 Taylor and Herzfeld 18 studied aggregation of polydisperse rigid spherocylindrical rods using scaled particle theory and obtained a temperature-concentration theoretical phase diagram in good qualitative agreement with the experimental one of Boden et al 13 However, as the authors note, including aggregate flexibility would vastly improve the model. The issue of rod flexibility was later addressed by Hentschke et al in their theoretical work.…”

Section: Introductionmentioning

confidence: 74%

“…This molecule was designed specifically to form only rod-shaped aggregates in aqueous solutions. 12,13 The mesophases formed by TP6EO2M in water have been extensively studied using proton NMR [12][13][14][15][16] , x-ray diffraction, 12,13 and DSC 14 across a wide range of concentrations and temperatures. In solution the molecules aggregate into small randomly-oriented stacks which, depending on temperature and concentration, self-organize into a variety of ordered phases.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Thermodynamics of the self-assembly of non-ionic chromonic molecules using atomistic simulations. The case of TP6EO2M in aqueous solution

et al. 2015

View full text Add to dashboard Cite

(2015) 'Thermodynamics of the self-assembly of non-ionic chromonic molecules using atomistic simulations.The case of TP6EO2M in aqueous solution.', Soft matter., 11 (4). pp. 680-691. Further information on publisher's website:http://dx.doi.org/10.1039/C4SM02275KPublisher's copyright statement:Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. ABSTRACTAtomistic molecular dynamic simulations have been performed for the non-ionic chromonic liquid crystal 2,3,6,7,10,11-hexa-(1,4,7-trioxa-octyl)-triphenylene (TP6EO2M) in aqueous solution. TP6EO2M molecules consist of a central poly-aromatic core (a triphenylene ring) functionalized by six hydrophilic ethyleneoxy (EO) chains, and have a strong tendency to aggregate face-to-face into stacks even in very dilute solution. We have studied self-assembly of the molecules in the low concentration range corresponding to an isotropic solution of aggregates, using two force fields GAFF and OPLS. Our results reveal that the GAFF force field, even though it was successfully used previously for modelling of ionic chromonics, overestimates the attraction of TP6EO2M molecules in water. This results in an aggregation free energy which is too high, a reduced hydration of EO chains and, therefore, molecular self-assembly into compact disordered clusters instead of stacks. In contrast, use of the OPLS force field, leads to self-assembly into ordered stacks in agreement with earlier experimental studies of triphenylene-based chromonics. The free energy of association follows a "quasi-isodesmic" pattern, where the binding free energy of two molecules to form a dimer is of the order of 3 RT larger than the corresponding energy of addition of a molecule into a stack. The obtained value for the binding free energy, ∆ agg G 0 = -12 RT, is found to be in line with the published values for typical ionic chromonics (-7 to -12 RT), and agrees reasonably well with the experimental results for this system. The calculated interlayer distance between the molecules in a stack is 0.37 nm, which is at the top of the range found for typical chromonics (0.33-0.37 nm). We suggest that the relatively large layer spacing can be attributed to the repulsion between EO side chains.2

show abstract

Section: Introductionmentioning

confidence: 74%

Section: Introductionmentioning

confidence: 99%

Thermodynamics of the self-assembly of non-ionic chromonic molecules using atomistic simulations. The case of TP6EO2M in aqueous solution

et al. 2015

View full text Add to dashboard Cite

show abstract

“…There are, however, other constraints in the system (the number of primary, small constituents, for instance), and these may induce new kinds of transitions characterized by the appearance of one or a few macroscopic aggregates. Such are phenomena as the appearance of lamellar and columnar phases in surfactant solutions [45], emulsification failure in micro-emulsions [46], or long chain formation in polymer solutions [47].…”

Section: Why Polydisperse?mentioning

confidence: 99%

Microstructure and macroscopic properties of polydisperse systems of hard spheres

Ogarko¹

View full text Add to dashboard Cite

“…Only few discoidal amphiphiles have been synthesized to date [7,8,10,[24][25][26]. They consist of disc-like hydrophobic central moieties (triphenylene [7,26], copper phthalocyanine [8], benzene [10,24], cyclotriveratrylene [25]) to which hydrophilic head groups are fixed directly.…”

Section: Structural Variations In Amphiphiles: Discoidal Multivalent mentioning

confidence: 99%

Structural variations in amphiphiles: Discoidal multivalent cations

Keller-Griffith¹,

Ringsdorf²,

Vierengel³

1986

Colloid & Polymer Sci

View full text Add to dashboard Cite

Fourteen cationic multipolar amphiphiles have been synthesized with pyridinium or trimethylammonium head groups. The hydrophobic cores are planar ring systems (benzene or triphenylene) to which two, three, four, or six decylene or undecylene alkyl chains are attached by ester linkages. The hydrophilic head groups are bound to the outer ends of the alkyl chains.The aggregation of the molecules in water into micelles and lyotropic liquid crystals has been studied. Hexagonal phases are preferred to lamellar phases by these amphiphiles and in more dilute solutions some of these muhipolar amphiphiles form cylindrical micelles.

show abstract

Phase behaviour and structure of a non-ionic discoidal amphiphile in water

Cited by 55 publications

References 14 publications

Thermodynamics of the self-assembly of non-ionic chromonic molecules using atomistic simulations. The case of TP6EO2M in aqueous solution

Thermodynamics of the self-assembly of non-ionic chromonic molecules using atomistic simulations. The case of TP6EO2M in aqueous solution

Microstructure and macroscopic properties of polydisperse systems of hard spheres

Structural variations in amphiphiles: Discoidal multivalent cations

Contact Info

Product

Resources

About